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46 <header><h1>Known Pitfalls (FAQ)</h1></header>
52 <h2><a name="Annotated_classes_in_dependencies_are_not_found."></a>Annotated classes in dependencies are not found.</h2>
55 hibernate4-maven-plugin by default scans dependencies in the scope
56 <tt>compile</tt>. You can configure it to scan dependencies in other
57 scopes as well. But it scans only direct dependencies. Transitive
58 dependencies are not scanned for annotated classes. If some of your
59 annotated classes are hidden in a transitive dependency, you can simply
60 add that dependency explicitly.
64 <h2><a name="hibernate4-maven-plugin_always_needs_a_database-connection"></a>hibernate4-maven-plugin always needs a database-connection</h2>
67 The default-configuration uses the EXPORT-target of the SchemaExport-Tool.
68 If you do not need to create a database with the evaluated schema, you can
69 use the NONE- or the SCRIPT-target.
70 This can be achieved with the command-line parameter
71 <tt>-Dhibernate.export.target=SCRIPT</tt> or with the following configuration:
75 <pre class="prettyprint linenums lang-html">
77 <target>SCRIPT</target>
78 </configuration></pre></div>
81 But even when no database is to be created, hibernate always needs to know
82 the dialect. Hence, the plugin will fail if this parameter is missing!
86 <h2><a name="Dependency_for_driver-class_XYZ_is_missing"></a>Dependency for driver-class XYZ is missing</h2>
89 One regular problem is the scope of the jdbc-driver-dependency.
90 It is very unlikely, that this dependency is needed at compile-time.
91 So a tidy maven-developer would usually scope it for <tt>runtime</tt>.
95 But this will break the execution of the <tt>hibernate4-maven-plugin</tt>.
96 Since it will not be able to see the needed dependency, it will fail with
97 an error-message like:
101 <pre class="prettyprint">
102 [INFO] Gathered hibernate-configuration (turn on debugging for details):
103 [INFO] hibernate.connection.username = sa
104 [INFO] hibernate.connection.password =
105 [INFO] hibernate.dialect = org.hibernate.dialect.HSQLDialect
106 [INFO] hibernate.connection.url = jdbc:hsqldb:/home/kai/mmf/target/mmf;shutdown=true
107 [INFO] hibernate.connection.driver_class = org.hsqldb.jdbcDriver
108 [ERROR] Dependency for driver-class org.hsqldb.jdbcDriver is missing!
109 [INFO] ------------------------------------------------------------------------
111 [INFO] ------------------------------------------------------------------------
112 [INFO] org.hsqldb.jdbcDriver
113 [INFO] ------------------------------------------------------------------------
114 [INFO] For more information, run Maven with the -e switch
115 [INFO] ------------------------------------------------------------------------
116 [INFO] Total time: 2 seconds
117 [INFO] Finished at: Thu Nov 29 11:31:14 CET 2012
118 [INFO] Final Memory: 32M/342M
119 [INFO] ------------------------------------------------------------------------</pre></div>
122 A quick workaround for this error would be, to delete the runtime-constraint
123 for the jdbc-driver-dependency.
127 A much cleaner way is, to (additionally) ad the dependency, to the
132 <pre class="prettyprint linenums lang-html">
134 <groupId>de.juplo</groupId>
135 <artifactId>hibernate4-maven-plugin</artifactId>
136 <version>1.1.0</version>
140 <goal>export</goal>
146 <groupId>org.hsqldb</groupId>
147 <artifactId>hsqldb</artifactId>
148 <version>2.2.8</version>
150 </dependencies>
151 </plugin></pre></div>
154 This is also the best way, if you use a different jdbc-driver for
155 testing, than in production.
156 Because otherwise, this dependency will unnecessarily bloat the
157 runtime-dependencies of your project.
160 <div class="section" id="fails">
161 <h2 id="fails">DBUnit fails after execution of hibernate4 was skipped because nothing has changed</h2>
164 If hibernate4-maven-plugin skips its excecution, this may lead to errors in
166 For example, when importing sample-data in the automatically created database
167 with the help of the <a class="externalLink" href="http://mojo.codehaus.org/dbunit-maven-plugin/">dbunit-plugin</a>,
168 the <tt>CLEAN_INSERT</tt>-operation may fail because of foreign-key-constraints,
169 if the database was not recreated, because the hibernate4-maven-plugin has
170 skipped its excecution.
174 A quick fix to this problem is, to <a href="./force.html">force</a>
175 hibernate4-maven-plugin to export the schema every time it is running.
176 But to recreate the database on every testrun may noticeable slow down your
177 development cycle, if you have to wait for slow IO.
181 To circumvent this problem, hibernate4-maven-plugin signals a skipped
182 excecution by setting the maven property <tt>$\{hibernate.export.skipped\}</tt> to
184 You can configure other plugins to react on this signal.
185 For example, the dbunit-plugin can be configured to skip its excecution, if
186 hibernate4-maven-plugin was skipped like this:
190 <pre class="prettyprint linenums lang-html">
192 <groupId>org.codehaus.mojo</groupId>
193 <artifactId>dbunit-maven-plugin</artifactId>
194 <configuration>
195 <skip>${hibernate.export.skipped}</skip>
196 </configuration>
197 </plugin></pre></div>
199 <div class="section">
200 <h2><a name="The_database_will_not_be_recreated_after_a_manual_dropclean"></a>The database will not be recreated after a manual drop/clean</h2>
203 If one manually drops the database or removes the hsqldb-files, it will not
204 be recreated by the hibernate4-maven-plugin, because it cannot detect, that
205 the database needs to be recreated.
206 This happens, because the plugin will not recreate the database if neither
207 the configuration nor the annotated classes have changed, because an
208 unnecessary drop-create-cycle might take a long time. The plugin will
209 report that like this:
213 <pre class="prettyprint">
214 [INFO] No modified annotated classes found and dialect unchanged.
215 [INFO] Skipping schema generation!</pre></div>
218 If one always uses <tt>mvn clean</tt> for cleanup, this will not happen.
219 Otherwise the recreation must be <a href="./force.html">forced</a>:
223 <pre class="prettyprint">
224 mvn hibernate4:export -Dhibernate.export.force=true</pre></div>
226 <div class="section">
227 <h2><a name="The_hibernate4:export_goal_is_not_executed_when_tests_are_skipped"></a>The hibernate4:export goal is not executed, when tests are skipped</h2>
230 The hibernate4-maven-plugin automatically skips its execution, when
231 <tt>maven.test.skip</tt> is set to <tt>true</tt>. If you need it to be always
232 executed, you can configure that explicitly like this:
236 <pre class="prettyprint linenums lang-html">
238 <groupId>de.juplo</groupId>
239 <artifactId>hibernate4-maven-plugin</artifactId>
241 <configuration>
242 <skip>false</skip>
243 </configuration>
244 </plugin></pre></div>
247 Background-information for this design-decission can be found on the extra
248 page <a href="./skip.html">To skip or not to skip: that is the question</a>...
251 <div class="section">
252 <h2><a name="I_do_not_want_my_dependencies_to_be_scanned_for_hibernate_annotations"></a>I do not want my dependencies to be scanned for hibernate annotations</h2>
255 If you do not want your dependencies to be scanned for hibernate annotations,
256 you can pass <tt>-Dhibernate.export.scan_dependencies=none</tt> to maven
257 or set <tt>scanDependencies</tt> to <tt>none</tt> in the configuration
258 of the plugin like this:
262 <pre class="prettyprint linenums lang-html">
264 <groupId>de.juplo</groupId>
265 <artifactId>hibernate4-maven-plugin</artifactId>
267 <configuration>
268 <scanDependencies>none</scanDependencies>
269 </configuration>
270 </plugin></pre></div>
272 <div class="section">
273 <h2><a name="No_annotated_classes_found"></a>No annotated classes found</h2>
276 If you are working under Windows and get the error-message
277 <tt>No annotated classes found in directory C:\projects\X Y Z\path-to-project\target\classes</tt>,
278 but you are really sure, that there are annotated classes in that
279 directory, you are expiriencing a bug, in the scannotation-library, that
280 was closed in version 1.1.0 of the hibernate-maven-plugin.
285 You should consider to upgrade to that version of the plugin.
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